The global rise of bacteria and other microorganisms resistant to antibiotics and antimicrobials in general, poses a major threat. Deployment of massive quantities of antimicrobial agents into the ecosphere during the past 60 years has introduced a powerful selective pressure for the emergence and spread of antimicrobial-resistant pathogens. Thus, there is a need to discover new broad spectrum antimicrobials, such as antibiotics, useful in combating microorganisms, especially those with multidrug-resistance.
Boron-containing molecules such as benzoxaboroles that are useful as antimicrobials have been described previously, see e.g. “Benzoxaboroles—Old compounds with new applications” Adamczyk-Woźniak, A. et al., Journal of Organometallic Chemistry Volume 694, Issue 22, 15 Oct. 2009, Pages 3533-3541, and U.S. Pat. Pubs. US20060234981 and US20070155699. Generally speaking, a benzoxaborole has the following structure and substituent numbering system:

Certain benzoxaboroles which are monosubstituted at the 3-, 6-, or 7-position, or disubstituted at the 3-/6- or 3-/7-positions are surprisingly effective antibacterials, and they have been found to bind to the editing domain of LeuRS in association with tRNALeu. Such compounds have been described in U.S. Pat. No. 7,816,344. Using combinations of certain substituted benzoxaboroles with norvaline and/or other amino acid analogs and their salts to: (a) reduce the rate of resistance that develops; and/or (b) decrease the frequency of resistance that develops; and/or (c) suppress the emergence of resistance, in bacteria exposed to compounds of formulas I and II, is described herein.